1. Field
The present invention relates to applicators for medicaments in stick formulations, and is more particularly directed to providing metered amounts of such formulations upon operation of a finger operable device.
2. State of the Art
Various substances are designed for topical use. That is, they are placed upon some portion of the outer surface of the body, and by some means, are caused to be adhered to or absorbed within the skin of the patient. Typical examples are liquids or lotions which are dispensed from a container onto the skin and are then rubbed into the skin with the fingers or hands. Substances of this type may be dispensed in liquid form with a roll-on applicator, such as is common with antiperspirants. Certain other such substances are commonly dispensed in "stick" form, such as is the case with lip balm and certain stick antiperspirants. This "stick" typically comprises a pillar of solid, waxy or semisolid substance dispensable, e.g. by means of a piston, from a tube. The substance typically is soft or melts at body temperature.
Certain topical medicaments may require more precise dosages than that which may be obtained by conventional topical application devices. Such medicaments may include drugs or other substances which in certain dosages have adverse side effects. For example, a solution containing minoxidil, used topically to stimulate hair growth, if used in greater quantities than prescribed, may result in reactions such as reduction in blood pressure, rapid heart rate (palpitations), weight gain, swelling, dizziness, pain, or indigestion.
Use of the hands or fingers in rubbing a substance into the skin is undesirable in circumstances in which the substance is potentially toxic or otherwise presents a hazard. In addition, waste of an expensive medicament by its unintended absorption into the hands is undesirable. An applicator capable of reliably dispensing and applying metered dosages is a desirable innovation.